Note: The number of buckets in a histogram is specified in the SIZE parameter of the SQL statement ANALYZE. However, the Oracle Database does not create a histogram with more buckets than the number of rows in the sample. Also, if the sample contains any values that are very repetitious, the Oracle Database creates the specified number of buckets, but the value indicated by this column may be smaller because of an internal compression algorithm.

LAST_ANALYZED

DATE

Date on which this column was most recently analyzed

SAMPLE_SIZE

NUMBER

Sample size used in analyzing this column

CHARACTER_SET_NAME

VARCHAR2(44)

Name of the character set: CHAR_CS or NCHAR_CS

CHAR_COL_DECL_LENGTH

NUMBER

Length

GLOBAL_STATS

VARCHAR2(3)

For partitioned tables, indicates whether column statistics were collected for the table as a whole (YES) or were estimated from statistics on underlying partitions and subpartitions (NO)

USER_STATS

VARCHAR2(3)

Indicates whether statistics were entered directly by the user (YES) or not (NO)

AVG_COL_LEN

NUMBER

Average length of the column (in bytes)

CHAR_LENGTH

NUMBER

Displays the length of the column in characters. This value only applies to the following datatypes:

CHAR

VARCHAR2

NCHAR

NVARCHAR

CHAR_USED

VARCHAR2(1)

B | C. B indicates that the column uses BYTE length semantics. C indicates that the column uses CHAR length semantics. NULL indicates the datatype is not any of the following:

CHAR

VARCHAR2

NCHAR

NVARCHAR2

V80_FMT_IMAGE

VARCHAR2(1)

Indicates whether the column data is in release 8.0 image format (Y) or not (N)

DATA_UPGRADED

VARCHAR2(1)

Indicates whether the column data has been upgraded to the latest type version format (Y) or not (N)

HIDDEN_COLUMN

VARCHAR2(3)

Indicates whether the column is a hidden column (YES) or not (NO)

VIRTUAL_COLUMN

VARCHAR2(3)

Indicates whether the column is a virtual column (YES) or not (NO)

SEGMENT_COLUMN_ID

NUMBER

Sequence number of the column in the segment

INTERNAL_COLUMN_ID

NUMBER

NOT NULL

Internal sequence number of the column

HISTOGRAM

VARCHAR2(15)

Indicates existence/type of histogram:

NONE

FREQUENCY

HEIGHT BALANCED

QUALIFIED_COL_NAME

VARCHAR2(4000)

Qualified column name

Footnote 1 These columns remain for backward compatibility with Oracle7. This information is now in the {TAB|PART}_COL_STATISTICS views.